Devices, systems, and methods for cooling a surgical instrument

ABSTRACT

An ultrasonic surgical instrument includes a waveguide defining a blade at a distal end thereof and a lumen extending through a portion of the blade. The blade is configured to receive ultrasonic energy for treating tissue. The instrument further includes first and second conduits each defining a proximal end and a distal end. The second conduit is coaxially disposed about the first conduit. The distal ends of the first and second conduits extend into the lumen. The distal end of the first conduit extends further distally into the lumen than the distal end of the second conduit.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No. 15/462,815, filed on Mar. 18, 2017, which claims the benefit of U.S. Provisional Patent Application Nos. 62/314,633 and 62/314,650, both filed on Mar. 29, 2016, the entire contents of each of the above-identified applications are hereby incorporated herein by reference.

BACKGROUND Technical Field

The present disclosure relates to devices, systems, and methods for cooling a surgical instrument and, in particular, to devices, systems, and methods for cooling a surgical instrument and systems and methods for controlling the same.

Background of Related Art

Energy-based tissue treatment is well known in the art. Various types of energy (e.g., electrical, ultrasonic, microwave, cryogenic, thermal, laser, etc.) are applied to tissue to achieve a desired result. Ultrasonic energy, for example, may be delivered to tissue to treat, e.g., coagulate and/or cut, tissue.

Ultrasonic surgical instruments, for example, typically include a waveguide having a transducer coupled thereto at a proximal end of the waveguide and an end effector disposed at a distal end of the waveguide. The waveguide transmits ultrasonic energy produced by the transducer to the end effector for treating tissue at the end effector. The end effector may include a blade, hook, ball, shears, etc., and/or other features such as one or more jaws for grasping or manipulating tissue. During use, the waveguide and/or end effector of an ultrasonic surgical instrument can reach temperatures greater than 200° C.

It would therefore be desirable to provide devices, systems, and methods for cooling a surgical instrument and controlling cooling of the same so as to enable cooling of the instrument without negatively impacting the use of the instrument.

SUMMARY

As used herein, the term “distal” refers to the portion that is being described which is further from a user, while the term “proximal” refers to the portion that is being described which is closer to a user. Further, to the extent consistent, any of the aspects described herein may be used in conjunction with any or all of the other aspects described herein.

Provided in accordance with aspects of the present disclosure is an ultrasonic surgical instrument including a waveguide defining a blade at a distal end thereof and a lumen extending through a portion of the blade. The blade is configured to receive ultrasonic energy for treating tissue. The instrument further includes first and second conduits each defining a proximal end and a distal end. The second conduit is coaxially disposed about the first conduit. The distal ends of the first and second conduits extend into the lumen. The distal end of the first conduit extends further distally into the lumen than the distal end of the second conduit.

In an aspect of the present disclosure, the instrument further includes a handle assembly including a movable handle, a jaw member positioned adjacent the blade, and an outer tube extending distally from the handle assembly and including the waveguide extending therethrough. The outer tube operably couples the jaw member and the movable handle such that actuation of the movable handle moves the jaw member relative to the blade from an open position to a clamping position.

In another aspect of the present disclosure, the instrument further includes first and second shaft members pivotably coupled to one another. One of the shaft members has a jaw member disposed at a distal end thereof, while the other shaft member supports the waveguide. One or both of the shaft members is movable relative to the other to move the jaw member relative to the blade between an open position and a clamping position.

In another aspect of the present disclosure, the blade defines a curved configuration.

In yet another aspect of the present disclosure, the first conduit is configured to supply fluid to the lumen, while the second conduit is configured to receive the fluid from the lumen.

In still another aspect of the present disclosure, the instrument further includes a splitter configured to receive the proximal ends of the first and second conduits. The splitter includes a first port and a second port, wherein the first port is disposed in fluid communication with the first conduit and the second port is disposed in fluid communication with the second conduit.

In still yet another aspect of the present disclosure, the first conduit is directly coupled to the first port of the splitter, and the second conduit is coupled to the second port of the splitter via a chamber defined within the splitter.

In another aspect of the present disclosure, the splitter further includes a drain port disposed in fluid communication with the chamber, and a stopper closing the drain port.

In yet another aspect of the present disclosure, a transducer assembly is operably coupled to the waveguide. The transducer may be releasably engagable with the waveguide or permanently affixed thereto.

A surgical system provided in accordance with aspects of the present disclosure includes an ultrasonic surgical instrument and a cooling module. The ultrasonic surgical instrument includes a waveguide defining a blade at a distal end thereof and a lumen extending through a portion of the blade. The blade is configured to receive ultrasonic energy for treating tissue. The instrument further includes first and second conduits each defining a proximal end and a distal end. The second conduit is coaxially disposed about the first conduit, and the distal ends of the first and second conduits extend into the lumen. The cooling module includes a pump operably coupled to the first and second conduits and configured to circulate fluid through the first and second conduits and the lumen to cool the blade.

In aspects of the present disclosure, the instrument may be configured similarly to any one or more of the aspects detailed above.

In another aspect of the present disclosure, the cooling module further includes a controller configured to control the circulation of fluid through the first and second conduits and the lumen to cool the blade.

In still another aspect of the present disclosure, the controller is configured for feedback-based control of the circulation of fluid through the first and second conduits and the lumen to cool the blade.

BRIEF DESCRIPTION OF THE DRAWINGS

Various aspects and features of the present disclosure are described hereinbelow with reference to the drawings wherein like numerals designate identical or corresponding elements in each of the several views:

FIG. 1 is a perspective view of a surgical system provided in accordance with the present disclosure including an endoscopic ultrasonic surgical instrument, a cooling module, and a cooling system incorporated therein;

FIG. 2A is an enlarged, perspective view of the area of detail indicated as “2A” in FIG. 1;

FIG. 2B is an enlarged, perspective view of the area of detail indicates as “2B” in FIG. 1;

FIG. 3 is an enlarged, perspective view of the distal end of the surgical instrument of FIG. 1;

FIG. 4 is a schematic illustration of the surgical system of FIG. 1 depicting the internal operating components of the cooling system thereof;

FIG. 5 is an exploded, perspective view of another surgical system provided in accordance with the present disclosure including a handheld endoscopic ultrasonic surgical instrument ultrasonic surgical instrument including an on-board cooling module and having a cooling system incorporated therein;

FIG. 6 is a side, cross-sectional view of an open ultrasonic surgical instrument provided in accordance with the present disclosure and including a cooling system configured for use therewith;

FIG. 7 is an enlarged, top, cross-sectional view of the blade of the surgical instrument of FIG. 6;

FIG. 8A is an enlarged, side, cross-sectional view of a portion of the surgical instrument of FIG. 6, illustrating routing of the cooling conduits into and through the waveguide of the surgical instrument;

FIG. 8B is a greatly enlarged, side, cross-sectional view of a portion of the surgical instrument of FIG. 6, illustrating the routing of the cooling conduits through the waveguide of the surgical instrument;

FIG. 9 is an enlarged, side view illustrating coupling of the cooling conduits of the surgical instrument of FIG. 6 with a tube splitter of the surgical instrument to enable the supply and return of cooling fluid from the surgical instrument;

FIG. 10A is a flow diagram depicting a method of cooling a surgical instrument provided in accordance with the present disclosure; and

FIG. 10B is a flow diagram depicting another method of cooling a surgical instrument provided in accordance with the present disclosure.

DETAILED DESCRIPTION

FIG. 1 depicts a surgical system 10 provided in accordance with the aspects and features of the present disclosure. Surgical system 10 generally includes an endoscopic ultrasonic surgical instrument 100 and a base unit 500 that, together, incorporate a cooling system for cooling a blade 162 of an end effector assembly 160 of endoscopic ultrasonic surgical instrument 100. Although detailed hereinbelow with respect to surgical system 10 and, more particularly, endoscopic ultrasonic surgical instrument 100 and cooling module 500 thereof, the aspects and features of the present disclosure are equally applicable for use with any other suitable surgical system, surgical instrument, and/or cooling module incorporating a cooling system. For example, the aspects and features may be provided for use in connection with a surgical system 20 including an endoscopic ultrasonic surgical instrument 1100 incorporating a cooling module 1500 thereon (see FIG. 5). Further still, another surgical instrument provided in accordance with the present disclosure, open ultrasonic surgical instrument 2100 (FIGS. 6-9), may similarly incorporate the aspects and features of the present disclosure. Obviously, different considerations apply to each particular type of system, instrument, and/or unit; however, the aspects and features of the present disclosure are equally applicable and remain generally consistent with respect to any such system, instrument, and/or unit.

Continuing with reference to FIG. 1, endoscopic ultrasonic surgical instrument 100 generally includes a disposable 102, a transducer and generator assembly (“TAG”) 200 including a transducer 210 and a generator 220 (FIG. 4), a battery 300, and a cable 400. Disposable 102 includes a housing 110, a handle assembly 120, a rotating assembly 130, an activation button 140, an elongated body portion 150, and end effector assembly 160. TAG 200 and battery 300 are releasably engagable with housing 110 of disposable 102 and, when engaged therewith, are disposed in electrical communication with one another such that power and/or control signals can be relayed between TAG 200 and battery 300 for operating instrument 100. TAG 200 may further include an indicator 202 disposed thereon, which will be described in greater detail below.

Elongated body portion 150 of disposable 102 of instrument 100 includes a waveguide 152 which extends from housing 110 to end effector assembly 160, an outer tube 154, and an inner tube (not shown). The distal end of waveguide 152 extends distally from outer tube 154 and defines blade 162 of end effector assembly 160, while the proximal end of waveguide 152 is operably coupled to TAG 200. Outer tube 154 is slidably disposed about waveguide 152 and extends between housing 110 and end effector assembly 160. Rotating assembly 130 is rotatably mounted on housing 110 and operably coupled to elongated body portion 150 so as to enable rotation of elongated body portion 150 and end effector assembly 160 relative to housing 110.

End effector assembly 160 is disposed at a distal end of elongated body portion 150 and includes blade 162 and a jaw member 164. Jaw member 164 is pivotable relative to blade 162 between an open position, wherein jaw member 164 is spaced-apart from blade 162, and a closed position, wherein jaw member 164 is approximated relative to blade 162 in juxtaposed alignment therewith for clamping tissue therebetween. Jaw member 164 is operably coupled to the distal end of outer tube 154 and the proximal end of outer tube 154 is operably coupled to movable handle 122 of a handle assembly 120, such that jaw member 164 is movable between the open position and the closed position in response to actuation of movable handle 122 of handle assembly 120 relative to fixed handle portion 124 thereof.

Blade 162 is configured to serve as an active or oscillating ultrasonic member that is selectively activatable to ultrasonically treat tissue grasped between blade 162 and jaw member 164. TAG 200 is configured to convert electrical energy provided by battery 300 into mechanical energy that is transmitted along waveguide 152 to blade 162. More specifically, TAG 200 is configured to convert the electrical energy provided by battery 300 into a high voltage alternating current (AC) waveform that drives the transducer (not shown) of TAG 200. Activation button 140 is disposed on housing 110 of disposable 102 and is electrically coupled between battery 300 and TAG 200. Activation button 140 is selectively activatable in a first position and a second position to supply electrical energy from battery 300 to TAG 200 for operating instrument 100 in a low-power mode of operation and a high-power mode of operation, respectively.

Referring to FIGS. 1-3, cooling inflow and return conduits 172, 174 extend from cooling module 500, through housing 110, and at least partially through outer tube 154 of elongated body portion 150 substantially along the length thereof. Proximal ends 173 a, 175 a of inflow and return conduits 172, 174, respectively, are operably coupled to cooling module 500, as detailed below (see also FIG. 4).

With particular reference to FIG. 3, distal ends 173 b, 175 b of inflow and return conduits 172, 174, respectively, extend into waveguide 152. More specifically, a lumen 166 is formed within waveguide 152 that extends through a portion of waveguide 152 including substantially along the length of blade 162 of waveguide. Lumen 166 defines a closed distal end. Conduits 172, 174 enter lumen 166 through an opening 168 defined within waveguide 152 and disposed in communication with lumen 166. A seal (not shown) disposed within opening 168 and around inflow and return conduits 172, 174 is provided to inhibit the escape of fluid thereform. Inflow conduit 172 is disposed within and extends distally through lumen 166. Return conduit 174 is disposed within the proximal end of lumen 166, although the above-detailed configuration of inflow and return conduits 172, 174 may be reversed. Inflow conduit 172 has a smaller diameter than lumen 166 leaving an annular gap 169 therebetween to permit the return of fluid to return conduit 174. As such, during cooling, fluid, e.g., water, saline, etc., is pumped through inflow conduit 172, exits a distal end of inflow conduit 172 at the distal end of lumen 166, and travels proximally back through lumen 166 within annular gap 169, ultimately being received by return conduit 174 for return to cooling module 500 (FIG. 1). Inflow and return conduits 172, 174 are at least partially formed from polyimide tubing. However, as it has been found that the portion of inflow conduit 172 that extends distally through lumen 166 may be subject to delamination and, as a flow, may block the flow of fluid during use. As such, in embodiments, the portion of inflow conduit 172 that extends distally through lumen 166 is formed from stainless steel or other material suitable to withstand high temperatures. Further, in embodiments where blade 162 is curved, the portion of inflow conduit 172 that extends distally through lumen 166 is likewise curved so as not to rub on the interior surface of blade 162.

Referring to FIG. 4, cooling module 500 includes an input port 510, a pump assembly 520, a controller 530, and a user interface 540. Input port 510 enables operable coupling of cable 400 with cooling module 500. More specifically, input port 510 includes an inflow conduit receptacle 512, a return conduit receptacle 514, and one or more electrical receptacles 516. Inflow conduit receptacle 512 operably couples inflow conduit 172 with pump assembly 520 upon engagement of cable 400 with cooling module 500, return conduit receptacle 514 operably couples return conduit 174 with pump assembly 520 upon engagement of cable 400 with cooling module 500, and the electrical receptacles 516 operably couple TAG 200 with controller 530, via wires 410, upon engagement of cable 400 with cooling module 500. Inflow and return conduit receptacles 512, 514 each include one or more sensors 513, 515, respectively, associated therewith for sensing the temperature of fluid flowing therethrough, the flow rate of fluid therethrough, and/or the presence of gas bubbles flowing therethrough, as detailed below.

Pump assembly 520 includes a fluid reservoir 522 and a pump 524 and is coupled between inflow conduit 172 and return conduit 174. Fluid reservoir 522 stores fluid to be circulated through conduits 172, 174 and lumen 166 to cool blade 162 of end effector assembly 160 (see FIG. 3) after use. In some embodiments, fluid reservoir 522 may be configured to regulate the temperature of the fluid retained therein. Further, instead of a closed system utilizing fluid reservoir 522, an open system may be provided wherein fluid to be circulated is received from an external fluid source (not shown), and fluid returning is output to a drain or return reservoir (not shown).

Pump 524 is configured as a pull-pump, wherein pump 524 operates to pull fluid through conduits 172, 174 and lumen 166. A pull-pump configuration is advantageous in that pressure build-up in push-pump configurations, e.g., due to an obstruction along the fluid flow path, is avoided. However, in some embodiments, pump 524 may be configured as a push-pump. Pump 524 may be a peristaltic pump, or any other suitable pump.

Continuing with reference to FIG. 4, controller 530 of cooling module 500 includes a processor 532 and a memory 534 storing instructions for execution by processor 532. Controller 530 is coupled to pump assembly 520, sensors 513, 515, TAG 200 (via wires 410 extending through cable 400), and user interface 540. Controller 530 may be configured to implement the method of FIG. 10A or 10B so as to instruct pump assembly 520 to turn pump 524 ON or OFF, to thereby initiate or stop blade cooling, based at least upon feedback received from sensors 513, 515, TAG 200, or other received feedback. As detailed below, controller 532 may be configured so as to instruct pump assembly 520 to turn OFF pump 524 where sensor 515 indicates a sufficiently low temperature of fluid returning from return conduit 174. The temperature of blade 162 (FIG. 3) of end effector assembly 160 may be extrapolated from the temperature of fluid returning from fluid conduit 174, or the temperature difference between the fluid entering inflow conduit 172 and that returning from return conduit 174, and, accordingly, pump 524 may be turned OFF upon blade 162 reaching a sufficiently cool temperature, e.g., below about 60° C. (or other suitable temperature threshold), as indicated by a sufficiently low return fluid temperature or sufficiently small temperature differential. As an alternative to sensors 513, 515 sensing temperature at input port 510, temperature sensors may be incorporated into pump assembly 520 for similar purposes as noted above. Further, in embodiments, a thermocouple 167 (FIG. 4) or other suitable temperature sensor may additionally or alternatively be incorporated into blade 162 (see, for example, thermocouple 2173 (FIG. 7)) to enable the sensing of temperature at blade 162.

Controller 530, as also detailed below with respect to FIGS. 10A and 10B, may additionally or alternatively instruct pump assembly 520 to turn OFF pump 524 or disable the entire system where sensor 513 and/or sensor 515 indicates an error. Such errors may include, for example, where sensor 513 and/or sensor 515 detects a flow rate through inflow conduit 172 and/or return conduit 174 below a threshold flow rate, and/or where sensor 515 detects gas bubbles, or a gas bubble volume greater than a threshold volume, returning from return conduit 174. Reduced flow rate and/or the presence of gas bubbles (or a greater volume of gas bubbles) may be an indication of a blockage or leak within the fluid flow path or damage to one of the conduits 172, 174 and, thus, the circulation of fluid is stopped by turning OFF pump 524 when such is detected. As noted above, in embodiments, rather than just turning OFF pump 524, the entire system is disabled, thereby inhibiting further use permanently or until the error or problem is remedied.

Controller 530 may further be configured, as also detailed below with respect to FIGS. 10A and 10B, to output an appropriate signal to user interface 540 and/or indicator 202 of TAG 200 to alert the user that blade cooling is in effect, e.g., that pump 524 is ON, that an error, e.g., a blockage or leakage, has occurred, and/or that blade 162 (FIG. 3) has been sufficiently cooled and is ready for further use. User interface 540 and/or indicator 202 may provide such an alert in the form of audible, visual, and/or tactile output.

Controller 530 may, additionally or alternatively, as also detailed below with respect to FIGS. 10A and 10B, be configured to communicate with TAG 200 to determine whether endoscopic ultrasonic surgical instrument 100 is in use, e.g., whether activation button 140 is actuated such that ultrasonic energy is being supplied to blade 162 (see FIG. 1), and to control pump assembly 520 in accordance therewith. More specifically, controller 530 may instruct pump assembly 520 to turn OFF pump 524 when endoscopic ultrasonic surgical instrument 100 is in use. Once use is complete, pump 524 may be turned ON for a pre-determined time, until blade 162 has been sufficiently cooled, until an error is detected, or until endoscopic ultrasonic surgical instrument 100 is once again put into use.

Controller 530 may further communicate with TAG 200 to control the cooling system and/or determine whether the cooling system is operating normally based on the frequency of the transducer 210 and/or waveguide 152 (FIG. 3). Thus, TAG 200 provides, e.g., via wires 410, the frequency of the transducer 210 and/or waveguide 152 (FIG. 3) to the controller 530. This frequency information is useful in that it is indicative of the state of the system. More specifically, it has been found that during use, e.g., during tissue treatment, the frequency decreases, while, upon deactivation and release of tissue, the frequency increases. It has further been found that, if waveguide 152 is cooled shortly after deactivation and release of tissue, the frequency increases at a significantly greater rate as compared to an un-cooled waveguide 152. Thus by monitoring the rate of change in frequency, e.g., by monitoring deviation of the rate of change relative to a threshold value or threshold range, controller 530 can determine whether the cooling system is working to effectively cool waveguide 152, or whether cooling is ineffective or inoperable. Such may be used in addition to or in place of temperature sensors. For example, the frequency information may be used, in conjunction with the flow rate information from sensors 513, 515, to determine whether cooling is working properly, based upon the flow rates and frequency rate of change, without the need to directly monitor temperature.

Turning now to FIG. 5, surgical system 20 is similar to surgical system 10 (FIG. 1) and generally includes an endoscopic ultrasonic surgical instrument 1100 and a cooling module 1500. However, rather than being coupled via a cable 400 as with endoscopic ultrasonic surgical instrument 100 and cooling module 500 (FIG. 1), instrument 1100 includes cooling module 1500 disposed thereon, e.g., formed as part of disposable 1102 or releasably mounted thereon.

Instrument 1100 generally includes a disposable 1102, a transducer and generator assembly (“TAG”) 1200 including a transducer 1210 and a generator 1220, and a battery 1300. Disposable 1102 includes a housing 1110, a handle assembly 1120, a rotating assembly 1130, an activation button 1140, an elongated body portion 1150, and an end effector assembly 1160, each of which are similar to the corresponding components of instrument 100 (FIG. 1), detailed above. TAG 1200 and battery 1300 are releasably engagable with housing 1110 of disposable 1102 and, when engaged therewith, are disposed in electrical communication with one another such that power and/or control signals can be relayed between TAG 1200 and battery 1300 for operating instrument 1100. TAG 1200 and battery 1300 are similar to those detailed above with respect to instrument 100 (FIG. 1), except as otherwise noted below.

Cooling module 1500, similar as with cooling module 500 (FIG. 4), includes input ports 1512, 1514, a pump assembly 1520, and a controller 1530. Cooling module 1500 may be permanently mounted on TAG 1200, may be releasably engagable with both TAG 1200 and disposable 1102, or may be permanently mounted on or within disposable 1102. Input port 1512 enables operable coupling of pump assembly 1520 with the conduits 1172, 1174 of instrument 1100, while input port 1514 enables communication between controller 1530 and generator 1220, both of which are similar as detailed above with respect to input port 510 (FIG. 4). Pump assembly 1520 and controller 1530 are also similar as detailed above, and may be configured to operate in a similar manner as mentioned above and as described in greater detail below.

Turning now to FIGS. 6-9, another instrument provided in accordance with the present disclosure, an open ultrasonic surgical instrument 2100, is detailed. Open ultrasonic surgical instrument 2100 is configured to operably coupled to a table-top generator (or other remote generator) (not shown) and a cooling module (similar to cooling module 500). In some embodiments, the generator and cooling module are integrated into a single housing (not shown). Open ultrasonic surgical instrument 2100 generally includes two elongated shaft members 2110 a, 2110 b, an activation button 2140, an elongated body portion 2150, an end effector assembly 2160, a tube assembly 2170, and a transducer assembly 2200.

Referring to FIG. 6, each shaft member 2110 a, 2110 b includes a handle 2111 a, 2111 b disposed at the proximal end 2112 a, 2112 b thereof. Each handle 2111 a, 2111 b defines a finger hole 2113 a, 2113 b therethrough for receiving a finger of the user. One of the shaft members, e.g., shaft member 2110 a, includes a jaw member 2164 of end effector assembly 2160 extending from the distal end 2114 a thereof. The other shaft member, e.g., shaft member 2110 b, supports elongated body portion 2150 and transducer assembly 2200 thereon. Shaft members 2110 a, 2110 b are pivotably coupled to one another towards the distal ends 2114 a, 2114 b, respectively, thereof via a pivot pin 2118.

Elongated body portion 2150 of shaft member 2110 b includes a waveguide 2152 (FIGS. 8A and 8B) which extends from transducer assembly 2200 to end effector assembly 2160, and an outer sleeve 2154 surrounding waveguide 2152. The distal end of waveguide 2152 extends distally from outer sleeve 2154 and defines a blade 2162 of end effector assembly 2160, while the proximal end of waveguide 2152 is operably coupled to transducer assembly 2200. Due to the pivotable coupling of shaft members 2110 a, 2110 b towards the distal ends 2114 a, 2114 b, respectively, thereof, handles 2111 a, 2111 b may be pivoted relative to one another to thereby pivot jaw member 2164 relative to blade 2162 between an open position, wherein jaw member 2164 is spaced-apart from blade 2162, and a closed position, wherein jaw member 2164 is approximated relative to blade 2162 in juxtaposed alignment therewith for clamping tissue therebetween.

Transducer assembly 2200 is configured to convert electrical energy provided by the generator (not shown) and supplied via cable 2210, into mechanical energy that is transmitted along waveguide 2152 to blade 2162. Transducer assembly 2200 may be permanently affixed to elongated body portion 2150 or may be removable therefrom. Activation button 2140 is disposed on one of the shaft members, e.g., shaft member 2110 b, and, similarly as detailed above with respect to instrument 100 (FIG. 1), is selectively activatable in a first position and a second position to supply electrical energy to transducer assembly 2200 for operating instrument 2100 in a low-power mode of operation and a high-power mode of operation, respectively.

With reference to FIGS. 7 and 8A-8B, elongated body portion 2150 is described in greater detail. As noted above, elongated body portion 2150 includes waveguide 2152 and outer sleeve 2154. The distal end of waveguide 2152 extends distally from outer sleeve 2154 and defines blade 2162. Waveguide is secured within outer sleeve 2154 via an O-ring 2156 (FIGS. 8A and 8B). As shown in FIG. 7, blade 2162 defines a curved configuration. Blade 2162 may be curved in any direction relative to jaw member 2164, for example, such that the distal tip of blade 2162 is curved towards jaw member 2164, away from jaw member 2164, or laterally (in either direction) relative to jaw member 2164. Waveguide 2152 and blade 2162 may include any of the features of waveguide 152 and blade 162 (see FIG. 3), and vice versa. Further, waveguide 2152 and blade 2162 may be used with instrument 100 (FIG. 1), or any other suitable instrument, and, likewise, waveguide 152 and blade 162 (see FIG. 3) may be used with instrument 2100 (FIG. 6), or any other suitable instrument.

Referring again to FIGS. 7 and 8A-8B, waveguide 2152 defines a lumen 2166 therethrough that extends into blade 2162. Lumen 2166 is open at its proximal end, the proximal end of waveguide 2152, and closed at its distal end, the closed distal end of blade 2162. Connection between waveguide 2152 and transducer assembly 2200 at the proximal end of waveguide 2152 serves to close off the proximal end of lumen 2166 (see FIG. 8A). Lumen 2166 defines a proximal segment 2167 a having the open proximal end and defining a first diameter, and a distal segment 2167 b having the closed distal end and defining a second diameter smaller than the first diameter.

Tube assembly 2170 (FIG. 6) includes inflow and return conduits 2172, 2174, respectively, and a tube splitter 2176 (FIG. 9). Conduits 2172, 2174 are arranged such that conduit 2174 is coaxially disposed about conduit 2172. Conduits 2172, 2174 enter proximal segment 2167 a of lumen 2166, in the above-noted coaxial arrangement, through an opening 2168 disposed in communication with lumen 2166. Inflow conduit 2172 extends distally from return conduit 2174 through proximal segment 2167 a of lumen 2166 into distal segment 2167 b of lumen 2166 to the distal end of blade 2162. Inflow conduit 2172 has a smaller diameter than distal segment 2167 b of lumen 2166 leaving an annular gap 2169 a therebetween to permit the return of fluid to return conduit 2174. Return conduit 2174 does not extend into distal segment 2167 b of lumen 2166. Rather, a ferrule 2175 is disposed about return conduit 2174 at the distal end of proximal segment 2167 b of lumen 2166 so as to seal an annular gap 2169 b of lumen 2166 surrounding return conduit 2174. As such, during cooling, fluid is pumped through inflow conduit 2172, exits a distal end of inflow conduit 2172 at the distal end of lumen 2166, and travels proximally back through lumen 2166 within annular gap 2169 a, ultimately being received by return conduit 2174. Ferrule 2175 inhibits further proximal flow of cooling fluid, e.g., into annular gap 2169 b, thus ensuring that the returning fluid enters return conduit 2174.

Referring to FIG. 9, tube splitter 2176 of tube assembly 2170 is disposed within one of the shaft members, e.g., shaft member 2110 b, of instrument 2100 (see FIG. 6). Tube splitter 2176 receives the proximal ends of conduits 2172, 2174 which, as noted above, are coaxially disposed relative to one another, and routes the flow of fluid to/from conduits 2172, 2174 and respective connector tubes 2182, 2184. Connector tubes 2182, 2184, in turn, are coupled with a cooling module (not shown, similar to cooling module 500 (FIG. 1)) to enable the inflow and outflow of cooling fluid to/from conduits 2172, 2174, similarly as detailed above with respect to instrument 100 (FIG. 1).

Tube splitter 2176 generally includes a housing 2190 defining a conduit port 2192, an interior chamber 2194, input and output ports 2196 a, 2196 b, respectively, and an auxiliary port 2198. Conduit port 2192 receives the proximal ends of conduits 2172, 2174 which, as noted above, are disposed in coaxial relation relative to one another. Return conduit 2174 is sealingly engaged within conduit port 2192 so as to inhibit the escape of fluid therebetween. Return conduit 2174 terminates at interior chamber 2194 and is disposed in fluid communication with interior chamber 2194. Inflow conduit 2172 extends through interior chamber 2194 and into input port 2196 a, wherein inflow conduit 2172 is sealingly engaged. Connector tube 2182 is sealingly engaged about input port 2196 a. Thus, fluid flowing through connector tube 2182 is routed into inflow conduit 2172 and, ultimately, through lumen 2166 (FIG. 7) of waveguide 2152 and blade 2162 (FIG. 7). Connector tube 2184 is sealingly engaged about output port 2196 b, which communicates with chamber 2194. As such, fluid flowing through return conduit 2174 ultimately flows into chamber 2194 and, thereafter, out through output port 2196 b to connector tube 2184. However, it is also contemplated that inflow and return conduits 2172, 2174, respectively, be reversed, and, thus, that fluid flows in the opposite direction. Auxiliary port 2198 communicates with chamber 2194 and includes a stopper 2199 sealingly engaged therein.

Tube splitter 2176 further includes sensors 2197 a, 2197 b disposed adjacent input and output portion 2196 a, 2196 b, respectively, although sensors 2197 a 2197 b may be positioned at any suitable position on or along instrument 2100 or the components thereof, e.g., the waveguide 2152, blade 2162, inflow and return conduits 2172, 2174, transducer assembly 2200, etc. (see FIGS. 6-8B). Sensors 2197 a, 2197 b may be configured as thermocouples for sensing temperature and/or may otherwise be configured similar to sensors 513, 515 (FIG. 4), respectively, to, as noted above, sense the temperature of fluid flowing therethrough, the flow rate of fluid therethrough, and/or the presence of gas bubbles flowing therethrough.

Referring to FIGS. 1 and 9, although detailed above with respect to instrument 2100 (FIG. 6), tube splitter 2176 and connector tubes 2182, 2184 may similarly be used in connection with instrument 100, serving to couple cooling module 500 and conduits 172, 174. In such a configuration, tube splitter 2176 is mounted within housing 110 of disposable 102 so as to receive the proximal ends of conduits 172, 174. Connector tubes 2182, 2184, in such a configuration, would extend through cable 400 for coupling with cooling module 500. Instrument 100 would otherwise be configured similarly as detailed above and would function in a similar manner as detailed above and described in further detail below.

Turning now to FIG. 10A, a method provided in accordance with the present disclosure, and applicable for use with instrument 100 (FIG. 1), instrument 1100 (FIG. 5), instrument 2100 (FIG. 6), or any other suitable ultrasonic surgical instrument incorporating or configured for use with a cooling system is described.

Initially, at S901, the end effector of the instrument is activated so as to supply ultrasonic energy to the end effector thereof to treat, for example, coagulate and/or cut, tissue. At S902 it is determined whether ultrasonic energy is still being supplied to the end effector. Such a determination may be performed, as noted above, by determining whether an activation button is activated. However, other suitable ways of determining whether ultrasonic energy is being supplied to the end effector are also contemplated, e.g., monitoring the output of the battery or the input to or output from the transducer. If it is determined that ultrasonic energy is being supplied, the determination at S902 is repeatedly made, periodically or continuously, until it is determined that ultrasonic energy is no longer being supplied to the end effector.

Once it is determined that ultrasonic energy is no longer being supplied to the end effector, the cooling system is activated as indicated in S903, to circulate cooling fluid through the end effector to cool the end effector. Likewise, an indicator S904 is provided to indicate that cooling is ongoing. During cooling, it is determined, at S905, whether the temperature of the end effector is below a threshold temperature. As noted above with respect to instrument 100 (FIG. 1), the temperature of the end effector may be determined indirectly by sensing the temperature of the fluid output to the end effector and returning therefrom. Such a configuration enables the use of temperature sensors remote from the end effector.

If the temperature of the end effector is determined to be above the threshold temperature, cooling continues at S903 and the temperature is continuously or periodically determined at S905. At the same time, an indicator, as indicated in S904, is provided to alert the user that cooling is still ongoing. Once the temperature of the end effector assembly is below the threshold temperature, as indicated in S906, cooling is deactivated and the indicator is removed. The threshold temperature, in some embodiments, may be about 60° C.

Referring to S907, during cooling, if an error is detected, cooling is deactivated at S906 and an indicator is provided at S904. Alternatively, the entire system may be shut down, inhibiting further activation or use, as indicated at S906′. An error may include, as noted above, a condition where the flow rate of fluid is below a flow rate threshold, a condition where the fluid includes gas bubbles or a sufficiently high volume of gas bubble, or other suitable error condition. The indicator provided in response to an error may be different from the indicator provided during cooling. If no error is detected, cooling continues at S903.

Turning to S908, during cooling, it is determined whether the supply of ultrasonic energy to the end effector has been activated. If so, cooling is deactivated at S909 and the method returns to S901. If the supplying of ultrasonic energy to the end effector has not been activated, the method returns to S903 and cooling is continued until the temperature of the end effector is below the threshold temperature, an error is detected, or the supply of ultrasonic energy to the end effector is activated.

Referring to FIG. 10B, another method provided in accordance with the present disclosure, and applicable for use with instrument 100 (FIG. 1), instrument 1100 (FIG. 5), instrument 2100 (FIG. 6), or any other suitable ultrasonic surgical instrument incorporating or configured for use with a cooling system is described.

The method of FIG. 10B is similar to that of FIG. 10A except that, during cooling, S913, it is determined at S914 whether the time cooling has been activated has reached a threshold time. If the cooling time has reached the threshold time, cooling is deactivated at S915. If the cooling time has not reached the threshold time, cooling continues at S913. Determination of the cooling time may be based upon an uninterrupted duration of cooling, a cumulative amount of cooling since the last energization of the end effector, or in any other suitable manner.

While several embodiments of the disclosure have been shown in the drawings and described hereinabove, it is not intended that the disclosure be limited thereto, as it is intended that the disclosure be as broad in scope as the art will allow and that the specification be read likewise. Therefore, the above description should not be construed as limiting, but merely as exemplifications of particular embodiments. Those skilled in the art will envision other modifications within the scope and spirit of the claims appended hereto. 

What is claimed is:
 1. An ultrasonic surgical instrument, comprising: a housing; a waveguide extending distally from the housing, the waveguide defining a blade at a distal end thereof and a lumen extending through at least a portion of the blade; an inflow conduit disposed in communication with the lumen, the inflow conduit configured to supply fluid to the lumen; a return conduit disposed in communication with the lumen, the return conduit configured to receive fluid from the lumen; a transducer engaged to the housing, the transducer coupled to the waveguide and configured to produce ultrasonic energy for transmission along the waveguide to the blade; a generator supported on or within the housing, the generator configured to drive the transducer; and a cooling module supported on or within the housing, the cooling module including: a pump assembly operably coupled to the inflow and return conduits via a first input port, the pump assembly including a fluid reservoir and a pump and configured to pump fluid from the fluid reservoir through the inflow conduit, into the lumen, and back through the return conduit to the fluid reservoir for cooling the blade; at least one sensor configured to sense at least one of a property of the fluid pumped into the inflow conduit or a property of the fluid returned from the return conduit; a controller configured to control the pump assembly according to the at least one sensed property; and a second input port configured to enable communication between the controller and the generator.
 2. The surgical instrument according to claim 1, wherein the cooling module is releasably engagable with both the housing and the transducer.
 3. The surgical instrument according to claim 1, wherein the cooling module and transducer are together releasably engagable with the housing.
 4. The surgical instrument according to claim 1, wherein the at least one sensor is configured to sense a temperature of the fluid returned from the return conduit.
 5. The surgical instrument according to claim 4, wherein the controller is configured to determine whether the blade has been cooled below a threshold temperature based upon the temperature of the fluid returned from the return conduit and to turn the pump assembly off when the blade is determined to have been cooled below the threshold temperature.
 6. The surgical instrument according to claim 4, wherein the at least one sensor is further configured to sense a temperature of the fluid pumped into the inflow conduit, wherein the controller is configured to determine a differential between the temperature of the fluid pumped into the inflow conduit and the temperature of the fluid returned from the return conduit and to turn the pump assembly off when the differential is below a threshold differential.
 7. The surgical instrument according to claim 1, wherein the at least one of the property of the fluid pumped into the inflow conduit or the property of the fluid returned from the return conduit indicates whether an error exists.
 8. The surgical instrument according to claim 7, wherein the at least one sensor is configured to sense at least one of a rate of flow of the fluid returned from the return conduit or a rate of flow of the fluid pumped into the inflow conduit, and wherein the controller is configured to determine whether an error exists based upon the at least one rate of flow.
 9. The surgical instrument according to claim 7, wherein the at least one sensor is configured to sense gas bubbles in the fluid returned from the return conduit or gas bubbles in the fluid pumped into the inflow conduit, and wherein the controller is configured to determine whether an error exists based upon the presence of gas bubbles.
 10. The surgical instrument according to claim 1, wherein the pump is a pull pump configured to pull fluid through the return conduit, the lumen, and the inflow conduit.
 11. The surgical instrument according to claim 1, wherein the ultrasonic surgical instrument further includes an indicator, and wherein the controller is configured to activate the indicator when the pump assembly is active.
 12. The surgical instrument according to claim 1, further including: a movable handle; a jaw member positioned adjacent the blade; and an outer tube extending distally from the housing and including the waveguide extending therethrough, the outer tube operably coupling the jaw member and the movable handle such that actuation of the movable handle moves the jaw member relative to the blade from an open position to a clamping position.
 13. The surgical instrument according to claim 1, wherein the transducer and generator together define a transducer and generator assembly that is releasably engaged to the housing.
 14. The surgical system according to claim 13, wherein the cooling module and the transducer and generator assembly are together releasably engagable with the housing.
 15. The surgical system according to claim 1, wherein the return conduit is coaxially disposed about the inflow conduit along portions thereof.
 16. The surgical system according to claim 1, wherein a distal end of the inflow conduit extends further distally into the lumen than a distal end of the return conduit. 